Komatsu Engine O-Ring Middle¤ Cylinder Liner 6127-21-2221

Komatsu Engine O-Ring Middle¤ Cylinder Liner 6127-21-2221 is a Komatsu engine replacement part listed by 19PARTS for engine-section lookup, hub navigation, and part-number verification.

Product overview

Part number 6127-21-2221 is listed as O-Ring Middle¤ Cylinder Liner. Search also by the no-dash alternate number 6127212221.

Engine book references

This part appears in Komatsu engine parts book paths such as:

• ENGINES / S4D155-4 S/N 10287-50040 / CYLINDER BLOCK / CYLINDER BLOCK(#10287-) (201)
• ENGINES / S4D155-4 S/N 10287-50040 / TOOL AND KIT / KIT(#10287-) (991)
• ENGINES / S6D155-4-R S/N 10014-UP / CYLINDER BLOCK / CYLINDER BLOCK (1/2)(#30551-) (201)
• ENGINES / S6D155-4-R S/N 10014-UP / ENGINE KIT / GASKET KIT(#56577-) (991)
• ENGINES / S6D155-4A S/N 10014-UP / CYLINDER BLOCK / CYLINDER BLOCK(#10014-19999) (1201)
• ENGINES / S6D155-4A S/N 10014-UP / CYLINDER BLOCK / CYLINDER BLOCK(#20000-) (1210)

This part appears in 60 Komatsu engine book paths in our reference data.

Verification note

Always confirm final fitment by engine model, serial range, diagram callout, and part number before ordering. Hub references are provided to help buyers find the right engine section and related parts faster.

Keep Ops Moving

19PARTS organizes Komatsu engine parts around searchable engine-model hubs so rebuild shops, equipment owners, and fleet teams can identify parts and keep repairs moving.